Field of the Disclosure
The present disclosure, for example, relates to wireless communication systems, and more particularly to signaling protocols to support multimedia broadcast operations in a wireless communication system.
Description of Related Art
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station). UEs may communicate directly with neighboring UEs using proximity service (ProSe) communication protocols.
A UE (e.g., an edge UE) may move out of coverage area of a base station and, instead, rely on a relay link with a neighboring UE (e.g., a relay UE) to continue communicating with the network. Generally, the edge UE may discover the existence of the neighboring UE using a ProSe discovery process and select the neighboring UE as a relay UE. The edge UE may establish a relay link with the relay UE in order for the traffic from the edge UE to be forwarded to the network, and so that traffic from the network can be relayed to the edge UE. The relay UE may support relay links with more than one edge UEs. Certain traffic types, e.g., multimedia broadcast multicast service (MBMS) traffic, may rely on multicast (one-to-many) transmissions. In the context of a ProSe relay link, it may be beneficial for a relay UE to be able to broadcast the multicast traffic to edge UEs rather than stream the MBMS traffic to each UE individually (e.g., unicast transmission). Current signaling protocols do not support such operations.